The present invention relates to an inkjet imaging device, capable of performing a recovery (maintenance) procedure that improves/recovers an ink ejecting condition of a recording head of the inkjet imaging device. The invention also relates to a method of controlling such an inkjet imaging device.
Conventionally, as an inkjet imaging device that ejects ink to recording medium such as a sheet of paper to form an image thereon, an inkjet printer is known. The inkjet printer typically includes a recording head unit which is provided with one or more recording heads and exchangeable ink cartridges for accommodating ink. The ink is supplied from the ink cartridge to the recording head, which selectively ejects the ink from a plurality of ink ejecting nozzles to form an image on the recording medium.
In the inkjet printer of the above type, when bubbles and/or foreign bodies reside inside an ink passage of the recording head, ejection of the ink may be blocked thereby, which deteriorates quality of the formed image.
A conventional inkjet printer is generally configured such that a recovery (maintenance) procedure for the recording head is executed when a user operates a predetermined switch and/or a predetermined condition is met. The maintenance procedure is for executing a purging operation, in which, a suction cap is placed on the nozzle surface and causes a negative pressure inside the suction cap using a suction pump, thereby the ink suctioned from the recording head is discharged outside the inkjet printer via the suction cap.
In the inkjet printer configured to execute such a maintenance procedure, in order to remove the ink adhered to the nozzle surface during the purging operation, a wiping operation and a flushing operation are further executed.
When the wiping operation is executed, a wiping member for removing (wiping out) the ink adhered onto the recording head is abut on the nozzle surface, while the recording head is moved with respect to the wiping member, thereby the nozzle surface of the recording head is wiped out.
When the wiping operation is executed, different color inks may be mixed among the nozzles for different colors. Therefore, the flushing operation for removing the mixed ink by ejecting the same is generally executed subsequent to the wiping operation. An example of such a sequence is disclosed in U.S. patent application Publication Ser. No. US 2002/000584 A1, teachings of which are incorporated herein by reference.
The inkjet printer operates in accordance with a predetermined sequence including a plurality of operation steps including the purging, wiping and flushing operations.
When the inkjet printer operates in accordance with a predetermined sequence to perform the maintenance procedure, if the maintenance procedure is forcibly stopped as, for example, a cancellation thereof is instructed by an operator, a problem as described below may arise. That is, when the sequence currently executed is interrupted during the maintenance procedure, the nozzle surface of the inkjet head is exposed to outside with the wet ink carrying thereon. When a print job is executed thereafter, an image may be blurred or faded. In order to avoid such a condition, some conventional inkjet printers are configured not to acquire the canceling instruction of the operator during the maintenance procedure. In such a configuration, since the maintenance procedure cannot be interrupted, the above problem is avoided.
Practically, however, the operator may intend to interrupt the maintenance procedure depending on a situation. In home-use inkjet printers or office-use ones, a time period for the maintenance procedure is relatively short. Accordingly, even though the maintenance procedure cannot be cancelled, the operator can wait for completion of the maintenance procedure. For commercial use inkjet printers for printing images on fabric such as T-shirts, however, the time period required for a maintenance procedure is relatively long in comparison with that for the home-use ones. Therefore, if the maintenance procedure cannot be cancelled, it is not only inconvenient but also it imposes the operator to wait for a relatively long time until the completion of the maintenance procedure.